火箭发射塔地震响应规律与减震性能分析

Analysis of seismic response rule and damping performance of rocket launch tower

火箭发射塔是在航天发射场执行火箭相关准备工作及发射任务的塔式结构。为探究火箭发射塔在地震作用下的响应规律,通过有限元仿真对火箭发射塔进行了动力特性分析及地震作用下的时程分析。研究结果表明:火箭发射塔的前2阶振型均为平动,第3阶振型为扭转,前6阶频率为1~5 Hz。在地震加速度幅值超过0.135g时,结构部分楼层层间位移角超出限值;结构各层加速度响应较大,对非结构构件的影响不可忽视,应开展相关减震研究;采用黏滞阻尼器作为火箭发射塔的减震装置,可有效降低结构的地震响应,对加速度响应有较好的控制效果;相同附加阻尼比下,满布方案的减震效果与集中布置方案差异较小。

The rocket launch tower is a tower structure that performs rocket-related preparation and launch tasks at a space launch site.In order to investigate the response law of rocket launch tower under earthquake,the dynamic characteristics and time history of rocket launch tower under earthquake were analyzed by finite element simulation.The results show that the first two vibration modes of the rocket launch tower are translational,torsion occurrs in the third mode,and the first six mode frequencies are 1-5 Hz.When the seismic acceleration amplitude exceeds 0.135g,some of the displacement angles between floors of the structure exceed the limit value.The acceleration response of each layer of the structure is large,which may lead to non-ignorable influence on non-structural components.The viscous damper is used as the seismic mitigation device for rocket launch tower and effectively reduces the seismic response of the structure,especially the acceleration response.With the same additional damping ratio,the mitigation effect of the fully distributed scheme is less different from that of the centralized scheme.